Steerable vehicle truck



Jan. 7, A. RQNNlNG STEERABLE VEHICLE TRUCK 5. 193s 2 sheets-sheet 1Original Fil sd Dec.

ATTORNEY A. RONNING STEERABLE VEHICLE TRUCK Jui. 11,941.

2 Sheets-Sheet 2 y I Original Filed Dec.

INVENTOR 4004 PH @GNN/N6 ATTORNEY Patents Nos.

Ressued Jan. 7, 1941 UNITED STATES PATENT OFFICE rial No. 244,019,December 5, 1938.

Application for reissue August 23, 1940, Serial No.

23 Claims.

This invention relates to steerable supporting units or trucks forWheeled vehicles, particularly of the self-propelled type, and theprimary object is to provide a novel, efficient, and practical means formounting a pair of closely spaced wheels so that they will steer about acommon or central vertical axis but yet have freedom for relativelyvertical or up and down movement to equalize load stresses to the twowheels, and whereby such equalizng or differential action will greatlyfacilitate the steering action particularly when the vehicle istraveling and making turns on uneven ground surfaces.

The original application, Serial No. 244,019, upon which this reissue isbased, is a continuation in part of my copending application Serial No.219,369, i'lled July 15, 1938, and for a disclosure .of other forms andmodifications oi' generally similar constructions attention is directedto my 2,208,599; 2,208,600; 2,209,093; 2,209,094; and 2,209,095, allissued on July 23, 1940. to my Patent No, 2,222,857 issued on November26, 1940; and to my Patents Nos. 2,217,816, 31,217,817 and 2,217,818,issued on October 15, 1940; and to my copendingl applications Serial No.259,361, filed March 2, 1939; Serial No. 311,330, flied December 28,1939; Serial No. 330,344, filed April 18, 1940; and Serial No. 332,763,filed May 1, 1940.

In the accompanying drawings, illustrating a preferred embodiment of thepresent inventive concept- Fig, 1 is a side elevation of the fore partof a tractor 'illustrating the application of my improved steeringtruck.

Fig. 2 is a front elevation of the tractor as shown in Fig. l, and witha part of the steering mechanism in section.

Fig. 3 is an enlarged front end elevation of the housing used inmounting the wheels, butwith the wheels removed from the extended stubshafts.

Fig, 4 is a side elevation of the housing with one side section removedto expose the differential mechanism.

Fig. 5 is a cross section through the housing and enclosed parts, as online 5-5 in Fig. 3.

Fig. 6 is a longitudinal vertical section through a modified form of thedevice.

Fig` 'I is a horizontal section on line 1-1 in Fig. 6.

Fig. 8 illustrates a tandem arrangement of tractors in which thesteerable truck of the rear tractor is attached to the draw bar of theforward tractor in such a manner that the tractors may (ci. 28o- 87)trail and be guided one behind the other and without interfering withthe vertical action of the truck wheels so guided.

The structure illustrated in Figs. 6 and 7, and applied in Fig. 8, isidentical with subject matter illustrated but divided out from myaforesaid application Serial No, 219,369, and to that extent the presentapplication is considered as a continuation in part from said otherapplication.

Referring to the drawings more particularly and by reference characters,A designates the frame of a tractor in the front end of which is secureda vertical bearing B in which is journaled a steering post C. At itsrear the tractor is provided with the usual transversely spaced tractionwheels D, as shown at the right in Fig. 8, which not only support therear end but also impart the necessary lateral stability. As shown inFig. 2, the upper end of post C has a worm gear E, operated by worm F onshaft G, and which shaft is in turn rotated by hand wheel H (Figs. 1 and8) manipulated by the tractor operator on seat I, When the tractors areoperated in tandem ,arrangement the steering-wheel H of the rear tractoris not used. In this case a draft link 9 connects the steerable truck ofthe rear ,tractor to the draw bar J of the front tractor so that theforward or angular position of the front tractor will guide such truckto steer the rear tractor, and in this case it may further be noted thatthe worm drive E-F is so pitched that the teeth will not lock but willbe free to rotate in response to the steering action imparted by theconnecting link 9. Referring now to Figs. 1-5, it will be seen that thebearing sleeve B is supported on the neck I0 of a housing I I made up oftwo complemental sections rigidly secured together by bolts I2. The neckportion I0 is rigidly secured to the lower end of the post so as to turnwith it about the post axis.

The ground wheels K, preferably of the pneumatic tire type, are closelyspaced inasmuch as they are not designed to give lateral stability tothe tractor and also because it is desirable to have them travel betweencrop rows when vthe tractor is to be used for row crop Work, Thesewheels Aare mounted on spindles I3, extending rigidly from the rear endsof crank arms I 4 and I5, disposed at opposite sides of the housing I Iand provided rat their forward ends with stub shafts I6 and Il,respectively, which extend coaxially into the housing and are journaledin anti-friction bearings I8 'I'he spindles I3 are slightly slopedoutwardly, as shown inFig. 3, to give the desired camber to the wheels,as indicated in Fig.

2. It should be noted, however, that any relative up and down movementof the wheels and cranks, about the axes of stub shafts I6-I1, will notdisturb either the fixed camber angle of the wheels or their relativeangle with respect to the steering post, nor will they produce anyrelatively transverse motion as between the wheels that would result intransverse frictional ground contact. It should also be noted that whilethe housing II projects forwardly from neck I0, the cranks I 4-I 5 bothextend rearwardly, with a result that the axes of the wheels K operatedirectly opposite the post C and in the vertical transverse planethereof, and consequently their positions or points of ground contactwill in no way resist the steering or wheel angling eort.

The inner ends of the stub shafts IB-II are rigidly splined, as shown inFig. 5, in bevel gear segments I8 and I9, respectively, and the gearsectors are operatively connected through an intermeshing, intermediatebevel gear pinion 20. This pinion has an integral stub extension 2|which journals in a bore 22 of the housing,y The member 20-2I may beconvenientlyv provided with a duct 23A by which oil contained in housingII may be conducted to the gearing bore 22 to lubricate the same.

It will be understood that as the weight of the front end of the tractoris imposed on the housing Ill-II it will be transmitted to the wheels Kthrough the gears I9-20, shafts IG-I'I, cranks I4-I5, and spindles I3,all of which will remain relatively stationary when traveling over levelterrain. When uneven ground surface is encountered, however, asindicated in Figs. 1 and 2, then the pinion 20 will differentiallyfunction to permit the wheels to assume relative vertical positions, onegear (I8 or I9) and its associated crank (I4 or I5) being free tooscillate upwardly while the other moves correspondingly downwardly,while at the same time continuing to distribute the applied tractorweight evenly to both wheels.

'I'here is, of course, a limit to the relative vertical movements of thewheels, and to eliminate objectionable Jars or'destructive contactswhenl .such movement limits are reached, I provide shock absorber orbumper in the form of springs 24 (Figs. 4 and 5). Each of these springsis anchored at its middle, as at 25, to the front wall of the housingIl, and its upper and lower ends extend resiliently forward to contactthe respective upper and lower ends of the adjacent gear segment andthereby yieldingly restrain forward movement thereof as the groundwheels approach their maximum limits of vertical movement.

It may here further be noted that the splining of the shafts I6 and I1in the respective gear segments is such that by removing nuts 26, afterhousing I I has been opened, the segments can be removed and resecuredon the shafts in selectively rotated positions, with a result that thecomposite :or normal working angles of cranks I4I5 may.

be adjusted when necessary. 'I'his adjustment is also of courseoperative to regulate the elevation of the tractor with respect to bothof the wheel spindles I3.

In the embodiment of the invention as exemplied by Figs. 6, '7, and 8,the gear case or housing 21 is of more elongated form than thatillustrated in Figs. 1-4 and has a.v neck 2l fixed to the lower end ofpost C by pin 23. The casing is preferably of solid or integralconstruction throughout except for a bottom opening shown as closed by acover plate 21a, secured by bolts 3|. In this instance the wheelcarrying assemblies include cranks 3| and 32, which support the Wheelspindles I3, and exten-d forwardly and rearwardly, respectively, fromthe hinge acting stub shafts 33 and 34 that are journaled in opposite,fore and aft ends of the housing, so that, as before, the axes of thewheels will be disposed centrally or in the transverse vertical plane ofthe steering post C.

Non-rotatably secured on the shafts 33, 34, and within the housing, is apair of spur gear segments 35, connected by an intermediate,intermeshing spur gear 36 which, it will be seen, has the samecompensating action or differential function as that described inconnection with the pinion 2li of Figs. 1-5. It may be noted that whilethe intermediate member 36 has been shown as a full gear, the extremeupper end lower teeth thereof (as seen in Fig. 6) at no time engage thesegments 35, and the gear portion which does connect the segments 35does so in the capacity and with the full effect of a rocker or lever,which lever is fulcrumed on the central pin that extends through it andis anchored in the side walls of the longitudinally extending housing21.

It will be noted that the housing closure plate 21a is provided with apair of depending lugs 3l adapted to receive bolts 38 which rigidlysecure to the plate a forwardly extending b ar 39. The rear end of draftbar 3 is pivoted to this bar 39, as at 40, so that the draftbar canswing vertically but when swung to either side will turn the housing 2lwith it to thereby steer the ground wheels K when the tractors areconnected in tanl dem as shown in Fig. 8. The forward end of the draftbar 9 is universallyconnected, as at 4I, to the draw bar J of thetractor so as to provide for 4the necessary flexibility of movement atthis point.

It may be mentioned that in the arrangement illustrated in Fig. 8 therear vehicle would not necessarily have to be a tractor as a steerabletruck embodying my improved features could as well be applied to anykind of drawn vehicle or 4 wheeled implement.

Referring back to-Figs. 3 and 4, it will be seen that I have there alsoprovided means in the form of a depending flange Ila, by which a similartrailer attachment might be connected with to i apply draft powerdirectly to the steerable truck in that case.

It is understood that suitable modifications may be made in thestructure as disclosed, provided such modifications come within thespirit an-d i scope of the appended claims. Having now therefore fullyillustrated and described my invention, what I claim to be new anddesire to protect by Letters Patent is:

l. In a vehicle, a steerable truck supporting e one end thereof andcomprising a pair of wheel supported cranks mounted for verticaloscillating movements about transverse centers in vertical planes, andfor steerable movements about a common vertical axis the transverseplane of e which is substantially coincident with a verticalplanethrough the axes of the wheels, and gear means differentiallyconnecting the cranks causing them to oscillate in opposite verticaldirections. 7

2. A steerable vehicle supporting truck comprising a member mounted foroscillation about a generally vertical axis to effect steering, a pairof cranks journaled in the member for simultaneous movement ltherewithabout said axis, ground 7 wheels rotatably secured .to said cranks. andgear means din'erentially connecting the journaled i ends of the cranksand operative to cause opposite up and down movements thereof and tocause the imposed vehicle weight to be transmitted lengthwise throughthe cranks and equally distributed to the wheels when and as the trucktravels overirregular ground surfaces.

3. A steerable vehicle supporting truck comprising a member mounted foroscillation about a generally vertical axis to effect steering, a pairof cranks journaled in the member for simultaneous movement therewithabout said axis, ground wheels rotatably secured to said cranks, gearmembers connected with 4the respective cranks, and an intermediate gea-rdifferentially connecting said gear members.

4. In a steering truck for vehicles, a mounting member rotatable aboutan upright axis, wheel supported members secured to the mounting member,one at each side thereof, for oscillating movements, and a gear traindifferentially connecting said wheel supported members.

5. In a steering truck for vehicles, a mounting member rotatable aboutan upright axis, a pair of wheel supported cranks carried at oppositesides of the member for oscillation about respective axes spaced withrespect to each other, a pair of gear segmentsconnected one with each ofsaid cranks, and a gear member interposed between and differentiallyconnecting said gear segments.

6. In a steering truck for vehicles, a mounting member rotatable aboutan upright axis, a pair of wheel supported cranks carried at oppositesides of the member for oscillation about a common axis, a pair ofopposed bevel gear segments connectedone with each crank, and a bevelpinion meshing with and differentially operating the gear segments.

7. In a vehicle, a mounting member, a pair of cranks oscillatablyjournaled in the mounting member, one at each side thereof, a pair ofgear segments attached to the respective cranks -to oscillate therewith,means for adjustably attaching one of the segments to the correspondingcrank whereby the crank and segment may be relatively adjusted about thecommon axis thereof, and a gear member differentially connecting thesegments.

8. In a vehicle adapted to be drawn. a steerable truck supporting thefront end .thereof and comprising a mounting member movable about avertical axis, a pair of wheels mounted one at each side of the memberfor opposite up and down movements while retaining predetermined faceangles with respect to said axis. means, op-

erative from a position on the vehicle, for turning the mounting tosteer thev wheels, and draft means, independent of said turning means,extending forwardly fromv the truck for applying pulling and steeringaction thereto.

9. A vehicle supporting device comprising a housing, a pair of wheelsupported crank arms iournaled in the housing, and gear means in thehousing dierentially connecting the journaled ends of the crank arms,said crank arms being iournaled for movement about longitudinally spacedaxes and extending in opposite directions therefrom.

10. In a vehicle, a pair of crank arms journaled at longitudinallyspaced outer ends with respect to the vehicle and with their inner endsseparately supported on axially aligned wheels, a pair of gear segmentsconnected with the respective cranks, and differential mechanismconnecting the arms within the housing .to move them and theirrespective wheels in opposite directions.

12. A steerable vehicle supporting truck comprising a member mounted formovement about a generally vertical axis to effect steering, a pair ofcranks fulcrumed in the member for simultaneous movements .therewithabout said axis, ground wheels rotatably secured to said cranks, and arotatable member differentially connecting.the cranks at a point nearerthe crank fulcrurns than are the axes of the ground wheels to the crankful-crums to oscillate the cranks and ground wheels in oppositedirections.

13. A steerable vehicle supporting truck comprising a member mounted formovements about a generally vertical axis to effect steering, a pair ofcranks journaled in ythe member for simultaneous movement therewithlabout said axis, ground wheels rotatably secured to said cranks and withtheir axes disposed approximately inv the .transverse plane through saidgenerally vertical axes, and a rotatable member differentiallyconnecting the cranks to oscillate the latter in opposite directions,said cranks being mounted for oscillating movements about a commontransverse axis and extending in the same general direction therefrom.

14. A steerable vehicle supporting truck comprising a member mounted forrotation about av vertical axis to effect steering, a pair of cranksjournaled in the member for simultaneous movetions, and gear means inthe housing dineren` tially connecting the cranks.

16. In a vehicle, a steerable truck therefor v comprising a housingmounted for turning movement about a generally upright axis, a pair oftransversely spaced wheel supported cranks journaled in the housing foroscillating movements in longitudinally extending planes, and y gearmeans in the housing differentially connecting the cranks, said gearmeans including gear elements connected to the respective cranks and anintermediate gear element connecting said gear l elements. y

17. In a vehicle, a steerable truck therefor comprising a housingmounted for turning movement about a generally upright axis, a pair oftransversely spaced wheel supported cranks Journaled in the housing foroscillating up and down movements, differentially acting gear meansconnecting the cranks, and yieldable stop means limiting the oscillatingmovements of the cranks, said stop means including a resilient membercooperatively associated with the gearmeans.

18. In a vehicle having a frame, a pair of crank arms pivoted withrespect to the frame for movements in transversely spaced paths, groundwheels rotatably secured to the arms, differential mechanism connectingpivoted ends i' the arms and operative to distribute imposed 'vehicle'weight equally through both'arms to the respective wheels, and means foradjusting the mean working angle of the arms with respect to thehorizontal.

19. In a vehicle having a frame, a pair of transversely spaced crankarms pivoted with respect to the frame for oscillating movements whilesupporting the frame, ground wheels rotatably secured to the arms, gearacting elements connected to the respective arms and at least one ofwhich elements is adjustable with respect to its arm so as to produceangular adjustments of both arms4 with, respect to the horizontal andthereby vertically adjust the frame, and a gear differentiallyconnecting said 'elements 20. In a vehicle, a longitudinal member rigidthroughout its length, a pair of wheel-carrying assemblies, a horizontalwheel-spindle in each assembly,`said wheel-spindles extending inopposite directions, said assemblies hinged to said member for up anddown movement in planes` spaced constantly .the same distance from saidmember, compensating means connecting said assemblies, said compensatingmeans including a rocker pivotally mounted on a rigid portion of thelongitudinal member.

21. In a vehicle, a longitudinal member rigid throughout its length, apair of wheel-carrying assemblies,` a horizontal wheel-spindle in eachassembly, said wheel-spindles extending in opposite directions, saidassemblies hinged to said member for up and down movement in planesspaced constantly the same distance from said member, compensating meansconnecting said assemblies, said compensating means including anoscillatable member mounted on a rigid portion of the longitudinalmember and in a position such that it will be intersected by atransverse vertical plane passing through the axes of saidwheel-spindles.

22. In a vehicle, a longitudinalmounting member, a pair oi.' wheelsupported cranks fulcrumed to the mounting member for movement of thewheels in transversely spaced parallel planes, compensating meanscontrolling relative movements of the cranks in said planes comprisingan oscillatable member fulcrumed to the mounting member for movementabout a transverse axis, and connecting members between the cranks andoscillatable member movable on axes parallel with respect to thetransverse fulcrum axis of the oscillatable member.

23. In a vehicle, a longitudinal mounting member, a pair oi' wheelsupported cranks fulcrurned to the mounting member for movement of theWheels in transversely spaced parallel planes, compensating meanscontrolling relative movements of the cranks in said planes comprisingan oscillatable member fulcrumed to the mounting member, and connectingmembers between the cranks and oscillatable member movable on axesparallel with respect to the fulcrum axis 0f the oscillatable member,said mounting member being of rigid construction whereby the fulcrumaxes for the oscillatable member and cranks will be retained inrelatively fixed positions.

ADOLPH RONNIN G.

